This was a study of the optimal dose, toxicities, and kinetics of an antisense oligonucleotide targed against protein kinase C alpha, a signaling protein thought to be important in the growth regulation of some cancers. Cohorts of three patients each were entered in to the study beginning at a dose of 0.5mg/kg/day for 21 day infusions. Twenty one patients have entered into this study in 5 cohorts of patients. Dose limiting toxicity was observed at the highest dose of 3.0 mg/kg/day, and consisted of severe fatigue as well as thrombocytopenia with clinically significant bleeding. The maximum tolerated dose was defined as 2.0 mg/kg/day over 21 days. Evidence of tumor response was observed in three of four patients with ovarian cancer. Steady state plasma levels of the antisense compound were achieved by 24 hours and were proportional to the dose administered. This study served as a foundation for three subsequent protocols including a Phase II study of antisense oligonucleotide alone in ovarian cancer, a Phase I stydy of a weekly infusion schedule, and a Phase I study of antisense with chemotherapy.